Twist, hand grip type throttle constructions for controlling a cable operated carburetor and of the type mounted on the handlebars of a motorcycle or the like have been in use for many years. These constructions generally comprise an elongate tubular hand grip which is adapted to be sleeved over the end of a handlebar and is rotatably mounted on the latter by means of a collar clamp assembly which includes a housing enclosing a spool like member fastened to the end of the hand grip for winding and unwinding the control cable thereon as the grip is twisted.
Some cycle-type vehicles powered by an internal combustion engine have heretofore been provided with a compression release device associated with the combustion cylinder of the engine in order to relieve pressure built up within the cylinder for purposes of facilitating starting of the engine or, permitting the vehicle to be pedaled in the case of the so-called "moped" type vehicles which include bicycle-type pedaling apparatus in addition to a gasoline powered engine. In the past, since the operation of the compression release device is independent of the normal throttle control, the hand operated operator controls for the compression release device have been mounted separately from the vehicle's ordinary throttle control and have necessitated the provision of a separate control cable and lever assembly or other means for operating the cable to actuate the compression release device. This prior art design is less than cost effective from a manufacturing standpoint due to the additional control levers and cables required, and poses an inconvenience to the vehicle operator in that he may have to remove one of his hands from the handlebars in order to reach the controls for effecting operation of the engine compression release; this poses an obvious safety hazard for the vehicle operator since the operator's hand should desireably remain on the handlebar grips at all times.